feat: Add Clickzetta Lakehouse vector database integration (#22551)

Co-authored-by: Claude <noreply@anthropic.com>

api/tests/integration_tests/vdb/clickzetta/README.md

@@ -0,0 +1,25 @@
+# Clickzetta Integration Tests
+
+## Running Tests
+
+To run the Clickzetta integration tests, you need to set the following environment variables:
+
+```bash
+export CLICKZETTA_USERNAME=your_username
+export CLICKZETTA_PASSWORD=your_password
+export CLICKZETTA_INSTANCE=your_instance
+export CLICKZETTA_SERVICE=api.clickzetta.com
+export CLICKZETTA_WORKSPACE=your_workspace
+export CLICKZETTA_VCLUSTER=your_vcluster
+export CLICKZETTA_SCHEMA=dify
+```
+
+Then run the tests:
+
+```bash
+pytest api/tests/integration_tests/vdb/clickzetta/
+```
+
+## Security Note
+
+Never commit credentials to the repository. Always use environment variables or secure credential management systems.